Sheet stacking apparatus



Nov. 5, 1968 H. R. BERGLAND 3,409,290

SHEET STACKING- APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet l m; Ia-rim (alum-mun u I N VENTOR.

BYHARRY R. BERGLAND.

A TTORNEY,

Nov. 5, 1968 H. R. BERGLAND 3,409,290

SHEET STACKING APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet z INVENTOR.

HARR) R. BERG'LAND.

Maw

ATTORNEY.

Nov. 5, 1968 H. R. BERGLAND 3,409,290

SHEET STACKING APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet 5 INV OR.

HARRY R. BER 0. BY

A T TORNE).

NOV. 5, 1968 BERGLAND 3,409,290

SHEET STACKING APPARATUS Filed NOV. 14, 1966 4 Sheets-Sheet 4 INVENTOR.

BY HARRY R. mam/m.

United States Patent hangar DisoLosuREQ Thedisclosure embodies "a highspeed'sheet stacking mechanisinof the'type in which sheets are fedsingly in sequential order into an expansible bin.

' [The invention resides in the provision of a sheet stacking bin havingone sidef formedby a movable member or belt carrying abutments orsockets to receive and guide the leading edges of the sheetsto the endof the bin to materially reduce sheet rebound and maintain sequentialorder of the sheets.

- One of the objects of the invention is to provide for a sheet handlingapparatus in which sheets are transported singly along a path of,travel, an improved high speed sheet stacking device of a structuralcharacter to eliminate the rebound of sheets from a bin end wall withoutneed of sheet shock absorbers. .fl-

Another object of the invention isto provide for a sheet handlingapparatus in which sheets are fed sequentially along a path of travel,an improved sheet stacking apparatus of a character to eliminate thestacking of sheets out of sequential order.

A further object of the invention is to provide an improved high speedsheet stacker in which each sheet is fed and under positive control toits stacked position as opposed to free flight stacking of sheets.

In connection with the next preceding object, it is a specific object ofthe invention to provide for a high speed sheet stacker, an endless beltforming one side of a stacking bin and carrying a plurality oflongitudinally spaced apart socket members to receive the leading edgesof respective sheets fed into the bin.

Other objects of the invention will become apparent from the followingdetail description, taken in connection with the'accompanying drawingsin which:

FIG. 1 is a plan view of the sheet stacking apparatus;

FIG. 2 is an elevational view partly in section, taken along the line2-2 of FIG. 1;

FIG. 3 is a horizontal sectional view, taken along the line 3-3 of FIG.2;

FIG. 4 is an enlarged fragmentary plan view showing a sheet in theprocess of being stacked;

FIG. 5 is a view similar to FIG. 4 showing the sheets advancement in thestacking operation;

FIG. 6 is a vertical sectional view, taken along the line 6-6 of FIG. 1,and

FIG. 7 is an enlarged horizontal sectional view, taken along the line7--7 of FIG. 6.

In the drawings, the numeral 10 designates a base plate on which ismounted a sheet feed transport system including a driven belt 12 and apressure belt 14. The belts 12 and 14 are of the endless type and arerelatively laterally positioned with opposed surfaces in broadsidecontact with each other to receive a sheet 15 therebetween. The belt 12travels about end drive and driven pulleys 16 and 18 respectively, and aguide pulley 20 is provided on the drive side of the belt 12 to maintaincontact between the belts. As shown in detail in FIG. 6, the pulley 16is afiixed onto a vertical driven shaft 22 which is suitably journaledon the base plate 10 where a suitable pulley 3,409,290 Patented Nov. 5,1968 and belt drive connection 24 may be used to connect the shaft to amotor 25. The pressure belt 14 travels about end pulleys 26 and 28 andis guided by intermediate guide pulleys 30 and 32. As shown in FIG. 1,'the guide pulley 32 is positioned to cooperate with the guide pulley'20to maintain the belts in contact with each other for gripping andfeeding sheets. The contacting sides of the belts 12 and 14 pass betweenspaced apart guide members 34 and 36 which guide sheets to an inlet 38to a sheet stacking bin, designated generally by the numeral 40.

The bin 40 includes a movable sheet back-up member 42 which extendslaterally of the direct-ionof travel of sheets into the bin by the belts12, 14, and thebin further includes an end Wall 44 which, in the presentconstruction, is carried by the back-up member. Springs 48 or othersuitable means may be employed to bias the back-up member 42 in adirection to yieldingly oppose increase in the sheet stack.

In accordance with the invetnion, a belt 50 is provided and arranged toform the sideof the bin opposite the back-up member 42 and carries aplurality of abutments or'socket forming members, or flexible tabs 52 toreceive the leading edges of sheets enroute to the bin. The belt 50travels about a pair of end pulleys 54 and 56 of which the pulley 54 isfreely rotatable on the driven shaft 22 and the pulley 56 is freelyrotatable on an upright fixed shaft 58, adjacent the bin end wall 44. Anintermediate guide pulley 59 is positioned to guide the belt 50 suchthat the belt travels longitudinally of the back-up member 42 from thebin inlet 38 toward and beyond the bin end wall 44. As shown, the tabs52 project into the bin 40 in a rearward direction with respect to thedirection of travel of the belt 50 at the bin, and the tabs formV-shaped sockets 60 with the belt proper. The flexible tabs provideexpansible-contractable sockets the purpose being to grip a leading endportion of a sheet as the tab is flexed inward by the pressure of theback-up plate and stack. Preferably, the belt 50 is made of a flexiblematerial, such as Mylar.

Further in accordance with the invention, the belt 50 is driven at aslightly less linear speed than the linear speed of the sheet feed belts12, 14 so as to insure that the leading edge of a sheet will engageand/or overtake one of the sockets 60. For example, on occasions a tab52 and the leading edge of a sheet may be in such timed relationshipthat the leading edge of the sheet would engage in a socket 60 at aboutthe tangency of pulleys 16 and 30. However, when the leading edge of asheet arrives at the tangency of pulleys 16 and 30 between a pair ofadjacent tabs 52, the above mentioned differential in linear speeds ofbelts 12 and 50 makes it possible for the feed belts to advance thesheet relative to belt 50 until the leading edge of the sheet engages inthe next preceding socket. The differential in linear speeds of the belt50 and the feed belts 12, 14 may be achieved by any suitable well knownmeans. In the present construction, shown in FIG. 6, the belt 50 isdriven from pulley 16 through a pair of integral pulleys 62 and 64 whichare freely rotatable on a fixed shaft 65, mounted in the base plate 10.The pulley 62 is driven from the pulley 16 by means of a belt 66 and theother or upper pulley 64 drives the pulley '54 through a drive belt 68.As shown, the upper pulley 64 is of lesser diameter than the lowerpulley 62 so as to effect a correspondingly lesser linear speed of belt50 than the linear speed of the sheet feed belts 12 and 14. It will nowbe appreciated that the leading edge of each sheet will lodge in asocket 60 of the relatively slower moving belt 50 without need ofprecise timing of the sheets and the sockets.

Operation In operation of the sheet handling apparatus, sheets are fedsingly into the guideway formed by members 34.

and 36 and are fed along the guideway by the belts 12, 14 toward theinlet 38 to the bin 40. As the belt 50 travels about the pulley 54, theresultant compression and tension on the inner and outer surfaces of thebelt causes the tabs 52 to flex outwardly into the sheet guideway in thepath of the leading edge of a sheet being fed along the guideway. Since,as previously mentioned, the feed belts 12, 14 travel at a higher linearspeed than the belt 50, the sheet is advanced relative to belt 50 untilthe leading edge of the sheet engages the next preceding socket 60. Thefeed belts 12, 14 continue to feed the sheet against the tab of theslower moving belt 50 which causes the sheet to bow, as illustrated inFIGS. 4 and 5. When the leading edge of the sheet strikes the end wall44 of the bin 40, the sheet is released from its socket as belt 50 movesbeyond the bin rear wall 44 The feed belts 12, 14 continue to feed andbow the sheet until the trailing end of the sheet is discharged from theguideway inlet and belt 14, at pulley 26 flips the end of the sheettoward the stack. As each sheet is added to the stack, the sheet back-upmember is moved outwardly by the increase in stack pressure thereon.This pressure also flexes the tabs 62 into the plane of the belt 50,whereupon the sheet is gripped and held between a tab 62 and the beltproper 50 with a force which opposes rebound of the sheet when thelatter strikes the bin end wall 44. At this time the tab starts to pullaway from the sheet and is still opposing the rebound tendency of thesheet. As previously mentioned, the tabs 62 are automatically flexedoutward as they pass around the pulleys 56 and 54 and thus one of thetabs is in position to receive the leading edge of a sheet entering thebin 40.

What is claimed is:

1. In a high speed sheet handling apparatus, apair of spaced apartlaterally disposed guide members defining a. substantially rectilinearpath of. travels-for.-sheetsafed singly therealong on edge, saidguideway having a sheet discharge end positioned at an acute angle tothe guideway, a pair of endless belts oppositely disposed along saidguideway to feed sheets therealong, a first driven pulley driving one ofsaid belts at a predetermined speed and positioned in the area definedby said acute angle, a second driven pulley having its axis of rotationcoincident with the axis of rotation of said first drum pulley andprojecting into the end portion of said guideway laterally of thelatter, a third endless belt extending around and driven by said seconddriven pulley and restricting said discharge, said third endless beltconstituting a moving feed side of a sheet stacking bin at an acuteangle to said guideway and driven at a speed less than the speed of saidone belt in the same direction as the latter, a plurality of spacedapart resilient members carried by said third belt on the outer sidethereof forming V-sockets to receive a leading edge portion of a sheet,and a sheet back-up member overlying the feed side of said third beltand biased to yieldingly flex said resilient members toward the plane ofthe feed side of said third belt.

References Cited UNITED STATES PATENTS 1,462,923 7/ 1923 Stevens 2 271-2,421,874 6/1947 Fouse 2716 9 3,167,012 l/1965 Claybourn 271-79 XFOREIGN PATENTS 700,816 12/1964 Canada. 191,863 2/1938 Switzerland.

EVON C. BLUNK, Primary Examiner. R. I. HICKEY, Assistant Examiner.

